This invention relates to a dovetail and slot assembly. In an embodiment the dovetail and slot assembly may be a part of furniture structures, for example a child's chair, consisting of substantially planar members which interlock without the use of tools or separate fasteners, and that are made from multi-layered, optionally recycled, corrugated or honeycomb Kraft (for example single face, single wall, double wall, triple wall), and that can be optionally recycled when no longer wanted by the consumer. The invention also relates to furniture structures or other structures that can pack flat during shipping, that are easy to assemble by the end-user without the use of tools or separate fasteners and that are made using multi-layer, optionally recycled, corrugated Kraft that is also optionally recyclable.
There has been a need in the art for lightweight, easy to assemble temporary structures including furniture and children's furniture. Other examples of structures include chairs, stools, tables, benches, shelves, items for loading products, display units, and packaging. In some cases it is desired to be able to recycle the item after it is used. Corrugated Kraft (for example cardboard) is a lightweight material. Items made from corrugated Kraft require special designing to provide rigid or strong structures.
Corrugated Kraft can be recycled, giving it a potentially sustainable complete lifecycle. The original Kraft can optionally be made from recycled material. The chair, for example, can be used for a period of time and then it can be recycled.
Cardboard is one generic term that can be used in place of Kraft, corrugated Kraft, corrugated cardboard, or flute. The art contains examples of cardboard structures with various assemblies and structural attachments and the art also contains examples of child's chairs made from tool-less assembly.
Another term that can be used in place of “corrugated Kraft” is “corrugated board”. Other terms in the art for corrugated structures include single face, single wall and double wall.
Some glues and coatings used on cardboard assemblies, for example glue used to combine several individual layers of corrugated Kraft to make a multi-ply sheet, are not compatible with recycling, in a process known as re-pulping. There is an industry standard testing procedure to determine if a glue or additive is compatible with re-pulping.
U.S. Pat. No. 4,556,253 (Geneve, Heiligenstein and Melamed) Teaches a disposable chair made from a single unitary die-cut and scored blank sheet of material.
Structures have been made from corrugated paperboard with certain structural members. U.S. Pat. No. 4,266,670 (Grigsby, Banks and Grigsby, Jr.) Teaches a collapsible reinforced container using a structural member formed from a billet. It also teaches a manufacture built up of corrugated paperboard sheets.
Modular knockdown furniture has been made from a kit of inter-fitting parts. U.S. Pat. No. 5,407,250 (Prince, Phillips, Hodge and Kitchen) teaches quick to assemble modular chair with a compact packing arrangement.
U.S. Pat. No. 5,263,766 (McCullough) teaches a unit of child's furniture such as a chair or sofa that is constructed of intersecting panels provided with a unique interlocking joint which provides strength, rigidity and long life to such furniture. In one form, each panel is made of a pair of triple wall corrugated cardboard sheets which are individually slotted and channeled to provide different portions of its joint, and which thereafter have their sides cemented together to form a double thickness corrugated panel. The furniture is preferably made so it can be transported and stored in flat, knockdown condition and assembled when needed.
US 2007/0102986 A1 (Buhrman) teaches a chair assembly kit comprising at least two end pieces, at least two middle pieces including a first middle piece as a chair back and a second middle piece as a chair seat, and at least four locking pieces. The middle pieces each include at least two tabs, one tab each on two opposing sides and each tab defining a hole. The end pieces each include at least two slots configured to receive the tabs on the middle pieces. The locking pieces each include at least two posts each having a detent mechanism, the posts being received in the holes in the middle pieces. The middle pieces selectively couple to the end pieces, and the locking pieces selectively lock the middle pieces to the end pieces via the detent mechanisms, to form a chair.
U.S. Pat. No. 5,387,027 (Maloney) teaches a furniture structure for chairs, benches and the like consisting of substantially planar members which interlock and reversibly unlock without the use of tools or separate fasteners, comprises two sides, a seat member, a back and a front, the sides each having an upper edge, and the seat member including a forward edge and a rear edge. An interlocking sector on each of the sides interlocks with the seat member, the back and the front without the need for tools or separate fasteners. The interlocking sector includes first and second members on each of the sides for frictionally engaging the forward and rear edges of the seat member, respectively, in opposite directions. A third member on each of the sides frictionally engages the seat member in a direction substantially perpendicular to the opposite directions. Back locks on each of the sides interconnect the back to each of the sides, and include an upper back lock and a lower back lock, The lower back lock is separated from the upper back lock at least by a distance equal to the distance between the upper edges of the sides when the structure is in a fully assembled condition. A front lock on each of the sides interlocks the front to each of the sides.
US 2012/0056463 A1 (Berent and Hulewat) teaches an article of furniture and associated methods and kits comprising at least one first leg support structure, at least one second leg support structure, the at least one first leg support structure being inter-fitted with the at least one second first leg support structure via an interference fit to define a support assembly, a top that is supported by and attached to the support assembly without the need for a mechanical fastener or adhesive; and means for creating a force state that attaches the top to the support assembly without the need for a mechanical fastener or adhesive, and thereby stabilizes the article of furniture, wherein the force state includes one or more forces applied to the at least one first leg support structure and the at least one second leg support structure, in addition to any frictional force from the interference fit.
US 2009/0066140 A1 (Berent and Hulewat) teaches an article of furniture and associated methods and kits comprising at least one first leg support structure, at least one second leg support structure, the at least one first leg support structure being inter-fitted with the at least one second first leg support structure via an interference fit to define a support assembly, a top that is supported by and attached to the support assembly without the need for a mechanical fastener or adhesive; and means for creating a force state that attaches the top to the support assembly without the need for a mechanical fastener or adhesive, and thereby stabilizes the article of furniture, wherein the force state includes one or more forces applied to the at least one first leg support structure and the at least one second leg support structure, in addition to any frictional force from the interference fit.
U.S. Pat. No. 7,219,962 B2 (Stone) teaches a furniture system comprising mutually supporting components including a pair of identically configured side panels, a load supporting panels and a back panel. The back panel engages the side panels and the load supporting panel to provide rigidity to the furniture item. A locking member is provided that holds the furniture item rigidly in an assembled condition.
U.S. Pat. No. 6,109,695 (Kahwaji) teaches a chair assembly having detachably interfitting parts. A right hand side support of the chair assembly includes slots extending from the exterior profile of the first side support towards the center of the side support. A left hand side support similar to the right hand side support is also provided. A seat pan having extensions is fitted into two complementary slots of the right and left side supports. A back support having extensions is also fitted into two complementary slots of the right and left side supports. The seat pan and the back support may be independently adjusted so as to present various sitting positions,
U.S. Pat. No. 8,112,868 B2 (Miller) teaches a method for manufacturing a chair assembly with a customized backrest includes fabricating a standardized frame, preparing a contoured plywood blank for the backrest, selecting a customized design for the backrest and then converting the design for the backrest into a readable format, loading the readable format for the backrest design into a customized cutting apparatus, loading the blank into the cutting apparatus, cutting the blank in conformity with the selected backrest design, removing the completed blank from the cutting apparatus, mounting the backrest onto the frame, and lastly, mounting a seat onto the frame.
One way to connect two cardboard members together is using a dovetail and slot. U.S. Pat. No. 5,836,254 (Johansson) teaches a pallet having a plurality of parallel base beams, and a deck joined to the plurality of parallel base beams. The deck includes a web or sheet of material, which is folded to form a deck surface with a plurality of parallel panels adjoining each other, and a plurality of parallel projections on an underside thereof. Each base beam extends upward to contact the underside of the parallel panels, and includes at least one through-recess having a shape which corresponds to a cross-section of a corresponding one of the plurality of parallel projections. The corresponding parallel projection engages the recess thereby forming the pallet with a plurality of spaces to accommodate lifting forks between the plurality of parallel base beams. Lower surfaces of the plurality of parallel projections form lifting surfaces for the lifting forks.
All of these references contain at least one of the following shortcomings: the item is not made from multi-layered corrugated Kraft, the item does not have a tool-less assembly, thus complicating the assembly process, the item does not have robust connections that form a long-lasting tight connection, the item does not have the aesthetically pleasing look and feel of natural wood, the item is not made from all materials (coatings, inks, glues) that are compatible with municipal recycling.
Recyclable manufactured items can be tested for water re-pulpability to certify recyclability. A standard test method is TAPPI Method UM 213 (2012) “Re-pulpability of splices/splicing tape”, and is incorporated by reference herein.
Thus, there is a significant need in the art for furniture structures for children that have at least one of the following traits: it is made from corrugated Kraft (lightweight, easy to ship), it has an easy, tool-less assembly, it is sturdy, it has the pleasing look and feel of natural wood, it can optionally be made from recycled material (and compatible with re-pulping), it is free-standing and can be moved without having to disassemble it. There is also a need in the art for sturdy, tool-less connections for structures made using substantially planar members made from layered corrugated Kraft.